From: Zheng Yan <zheng.z.yan@intel.com>
Date: Mon, 19 Sep 2011 02:37:34 +0000 (-0400)
Subject: tcp: fix validation of D-SACK
X-Git-Tag: v3.0.5~60
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=616ea55abc53ced58c4097b33b26abea01a743d4;p=karo-tx-linux.git

tcp: fix validation of D-SACK

[ Upstream commit f779b2d60ab95c17f1e025778ed0df3ec2f05d75 ]

D-SACK is allowed to reside below snd_una. But the corresponding check
in tcp_is_sackblock_valid() is the exact opposite. It looks like a typo.

Signed-off-by: Zheng Yan <zheng.z.yan@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index bef9f04c22ba..b6771f9eb9d4 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1115,7 +1115,7 @@ static int tcp_is_sackblock_valid(struct tcp_sock *tp, int is_dsack,
 		return 0;
 
 	/* ...Then it's D-SACK, and must reside below snd_una completely */
-	if (!after(end_seq, tp->snd_una))
+	if (after(end_seq, tp->snd_una))
 		return 0;
 
 	if (!before(start_seq, tp->undo_marker))